1. Field of the Invention
The present invention generally relates to electrodeless lamps, and more particularly, to configurations of cores surrounding lamp envelopes of electrodeless lamps.
2. Description of the Related Art
Various types of electrode lamps are available that have lamp electrodes disposed within a lamp envelope to deliver electrical power to the lamp. For example, in electrode type fluorescent lamps and incandescent lamps, electrical power is delivered to a lamp through electrical power flowing between the lamp electrodes.
Recently, there have been introduced various types of electrodeless lamps that do not require electrodes disposed within the lamp envelope. One of the advantages of not using electrodes in electrodeless type lamps is that the life of the lamp can be substantially extended since the use of an electrode is a major factor in limiting the life of electrode type lamps.